Saw a flock of about 15 of these small birds with red faces, black and white tails and yellow side feathers all feeding as a group in my garden this morning, systematically stripping it of food. Each is about half the size of a robin which was also grazing and appeared quite scared of such a large group. The below photo doesn't do the sight justice, in hindsight should have used the 4k video and started recording much sooner. Google says the bird is called a goldfinch.